LTT: Aditya Jha - The Anatomy of Thermal Equilibrium and Fluctuation Theorems

The Center for Philosophy of Science at the University of Pittsburgh invites you to join us for our Lunch Time Talk. Attend in person at 1117 Cathedral of Learning or visit our live stream on YouTube at https://www.youtube.com/channel/UCrRp47ZMXD7NXO3a9Gyh2sg. LTT: Aditya Jha Tuesday, October 6th @ 12:00 pm - 1:30 pm EST Title: The Anatomy of Thermal Equilibrium and Fluctuation Theorems Abstract: In this talk, I explore the relationship between various fluctuation theorems and the Second Law in statistical thermodynamics and argue against a commonly held perception, namely that fluctuations somehow constitute a "violation" of the Second Law. I instead suggest that the Second Law restricts the statistical form of fluctuations not only in equilibrium regimes but also in far-from-equilibrium regimes. This restriction, I show, emerges from the anatomy of statistical (thermal) equilibrium, which, properly understood, is a conjunction of three conditions: the stationarity of an ensemble, its detailed balance, and a compositional condition on energies and probabilities, grounded in the operational content of the Second Law, that forces probability to be logarithmically linear in energy. I demonstrate how fluctuation theorems exploit this anatomy: in equilibrium through the global detailed balance of the system itself, and in far-from-equilibrium regimes through local detailed balance, a condition that the thermal environment imposes locally on a system's coarse-grained transitions without the system itself being in equilibrium. This talk will also be available live streamed on: Zoom at https://pitt.zoom.us/j/98055239588 YouTube at https://www.youtube.com/channel/UCrRp47ZMXD7NXO3a9Gyh2sg.